What causes someone stress is individually very different. Just as different are the recipes that help against it, and often even a small interruption has a great effect. These are the principles according to which an app works, developed by scientists at the University of Duisburg-Essen (UDE). They want to find out how mobile applications on smartphones can increase resilience to stress and thus improve mental health. They are now looking for test persons who are prepared to use the app for at least two weeks.